Dipper teeth



P 1960 T. A. RATKOWSKI 2,951,300

DIPPER TEETH Filed Sept 19, 1956 INVENTOR.

THU/VH5 Fl. R'H TKUWEK/ United States DIPPER TEETH Thomas A. Ratkowski, Chicago Heights, 11]., assignor to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Filed Sept. 19, 1956, Ser. No. 610,735

9 Claims. (Cl. 37-142) This invention relates to a dipper tooth for excavating equipment.

Dipper teeth such as those which are projectably mounted on the lip of an excavating shovel or the like are sometimes in the form of a hollow cap or so-called point removably mounted on an adapter which in turn includes a shank for attachment to the excavating shovel, this construction enabling the adapter to be repointed when the cap becomes unduly worn. There have been various proposals set forth with respect to the way in which the cap is to be retained on the adapter, inasmuch as it .is essential that the point be prevented from shifting or rolling on the adapter during operation of the shovel.

Among the retainers proposed have been pins that are to be passed horizontally transversely through aligned ways in the cap and the adapter. In some instances a coil spring is used to hold the pin in position, and relatively complicated construction is required for housing the spring. Moreover, extensive efiort is required to assemble and disassemble the tooth, and for this reason such retainers have not been found altogether satisfactory.

Other proposals for retaining the cap on the adapter have entailed a pin inserted. in transverse horizontal grooves afforded respectively in the top of the cap and the top of the adapter which are designed to mate and afford a key-way when the cap is on the adapter, and it has been proposed to afford a resilient element to hold the pin within such a key-way. In an arrangement of this kind, neither the groove in the cap nor the groove in the adapter is closed on all sides, and this accounts for a tendency of the pin to work loose or allow movement of the cap relative to the adapter. Retainers of this kind are not readily permissive of reversible points, whereas it is desirable that the retainer resorted to be of a kind enabling this to be accomplished.

Still other proposals have involved a pin that is to be passed vertically through openings in the cap and a keyway in the adapter, and in this connection it has been proposed that the pin be engaged by a coil spring or a compressible rubber boss in the adapter tending to apply an unbalanced rearward torque to the end of the pin reposed in the upper opening of the cap. While such serves in some measure to pull the top of the cap up on the adapter, it will be recognized that this force applied at the top of the pin tends at the same time to turn the opposite end of the pin in a forward direction.

In view of the foregoing, the primary object of the present invention is to removably mount the cap of a dipper tooth on the adapter by a pin located in a vertical key-way afforded by aligned openings at the vertical center-line of the cap and adapter, the pin being retained or held in position by a filled leaf spring in such a manner that the action of the spring is equally distributed accountingfor uniform forces holding the cap to the adapter. Yet more specifically, objects of the present invention are to assure that the aforementioned spring acts on the pin in such a manner as to pull the cap up on the adapter with equal force at the top and bottom of the cap as afforded i 2 by a rearward compressive force distributed equally with respect to the pin along the horizontal center line of the cap and adapter, and to fill the spring with resilient material such as rubber or the like to assure that the spring will not become clogged and lose its effectiveness.

More specifically, it is an object of the present invention to enable the point of a dipper tooth to be removably and reversibly held on the adapter in an effective manner by a separable pin and rubber filled leaf spring of relatively uncomplicated complemental arrangement so that individual mounting and dismounting of the parts may be accomplished with facility.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments of the present invention and the principles thereof and what I now consider to be the best mode in which Ihave contemplated applying these principles. Other embodiments of the invention embodying the same or equivalentprinciples may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

Fig. 1 is an exploded perspective of one form of cap and adapter contemplated by the present invention;

Fig. 2 is a plan view showing the cap and adapter of Fig. l in assembled relation;

Fig. 3 is a side elevation of the assembly shown in Fig. 2; v

Fig. 4 is a perspective view, partly sectioned, of the filled spring; and

Fig. 5 is a perspective view of the retainer pin. 7 i The dipper tooth illustrated in Figs. 1 to 3 includes a wedge-shaped cap or so-called point 30 that is to be removably and reversibly mounted on an adapter 31. As shown in Fig. 3, the cap 30 includes spaced apart flat upper and lower walls 34 and 35 that converge in a forward direction to afford a digger point 36 and in this instance the digger point is provided with a chamfered upper edge 37 and an opposed lower edge portion 38 inclined downwardly at an angle to the plane of the lower wall 35 as shown in Fig. 3. Such construction of the lower edge portion of the digging point of the tooth affords in effect what constitutes surplusage metal so that as the digging point becomes worn the cap may be removed from the adapter and reversed face for face as is well known in the art.

The cap 30 in the present instance also includes parallel spaced apart side walls 41 and 42, Figs. 1 and 2, of triangular shape cast integral with the upper and lower walls 34 and 35. The divergent spacing between the inner faces of the upper and lower walls 34 and 35 affords a forwardly tapered rearwardly opening socket enabling the cap to be mounted tightly on a complementary wedgeshaped nose 45 of the usual kind projecting forwardly at the front of the adapter 31, the depth of the socket in the cap 30 included between the walls 34 and 35 corresponding substantially to the length of the adapter nose. The base of the adapter nose 45 is filleted at 45F, Fig. 2, and the base of the cap is likewise filleted at 30F. These filleted surfaces are normally in spaced relation when the cap is on the adapter as shown in Figs. 2 and 3 for a purpose to be described.

The adapter 31 includes an elongated rearwardly extending shank 46 formed with a vertical opening 47 utilized for mounting the dipper tooth on the dipper in the usual manner, and intermediate the nose 45' and the shank 46 are spaced apart upper and lower overhanging flanges 51 and 52 which when the tooth is mounted in operative position fit around edge portions of the dipper lip.

It will be recognized that both the cap and adapter are one-piece castings of manganese steel or like ferrous alloy having high resistance to wear and impact, and during the casting operation the nose of the adapter in accordance with the present invention is cored to provide an enlarged recess 55, Fig. 1, extending vertically therethrough from one face to the other. Opening into the recess 55 are a pair of spaced apart upper and lower rearwardly extending sockets 57 and 58, Fig. 3, having dead ends within the body of the adapter, and these sockets are adapted to receive rearwardly projecting tangs or lugs 57A and 58A cast medially at the rear edges of the upper and lower walls 34 and 35 of the cap 30. These lugs include portions as 58M, Fig. l, that extend inwardly of the inner faces of the upper and lower walls of the cap and where lugs of this kind are provided such assure rigidity between the point and the adapter, but lugs. not inclusive of rearwardly projecting portions may be used for this purpose as described in application Ser. No. 522,050, filed July 14, 1955, now Patent No. 2,904,908.

As shown in Fig. 3, the lugs 57A and 58A when the cap is on the adapter extend back into the sockets 57 and 58 and normally terminate short of the dead ends thereof. This relation is attained by dimensioning the parts so that when the cap is on the adapter the forward rounded apex 45E of the nose 45 is normally spaced from the forward rounded apex 30E of the socket in the cap as shown in Fig. 3, enabling take-up or creep to occur during extended use of the tooth to the extent that the filleted surfaces 30F and 45F finally mate.

Projecting forwardly medially between the mounting sockets 57 and 58 is a relatively large boss 59, Fig. 3, and the end of this boss defines the rear wall of a vertical key-way 60, Figs. 1 and 3, within the nose of the adapter. The cap 30 includes openings 62 and 63 in the upper and lower 'walls thereof, respectively, which when the cap is on the adapter register with the key-way 60 as shown in Fig. 3. The lugs 57A and 58A extend forwardly into the socket in the cap 30 to the extent that the forward ends .of these lugs are common to the rear walls of the openings 62 and 63 as is apparent in Figs. 1 and 3.

To hold the cap on the adapter in accordance with the present invention, a pin 65 of the kind shown in Fig. is to be passed downwardly through the upper of the openings in the cap 30 aligned with key-way '60 to the .extent that the upper and lower ends of the pin 65 repose in the upper and lower openings 62 and 63 in the cap 30, and a generally C-shaped leaf spring 66 of the. kind shown in Fig. 4 is disposed within the recess 55 in. the adapter to act between the forward face of the pin and a vertical portion within the adapter forwardly thereof to hold the cap on the adapter as will be described.

To enable the foregoing to be achieved in accordance with the present invention, a rearwardly projecting mounting boss 68 is cast medially on the front wall of the recess fining in effect the front wall of'the key-way 60. The boss 68, as shown in Fig. 3 is of reduced thickness relative to the depth of the recess 55 such as to afford a rearwardly facing vertical portion within the adapter in the form of identical upper and lower shoulders 71 and 72 forwardly of the pin 65 in the key-way. The leaf spring 66 is of relatively strong characteristics insofar as compressive strength is concerned, and this spring is preferably formed to include reversely inwardly bent end portions as 66E, Fig. 4, intermediate or medial outwardly curved nodal portions as -66N and a rearwardly curvedarcuate back portion or rear node 66B, the relation being such that the spring is symmetrical in shape. The shoulders 71 and 72 are exposed at either face of the nose of the adapter, and the ends 66E of the spring 66 are spaced apart sufii- 'ciently to enable the spring to be mounted on the boss .55 within the adapter at the center line thereof thus de- 68 with the free end portions thereof abutting these vertical portions 71 and 72 as shown in Fig. 3.

The spring 66 is first mounted in this manner on the boss 68 within the recess 55 of the adapter independently of the pin 65 and when so positioned the arcuate back 66B thereof projects rearwardly beyond the boss 68 well into the key-way 60. The cap is next positioned on the adapter with the openings 62 and 63 thereof registered with the key-way 60, whereupon the pin 65 which is a separable part with respect to the spring 66 is driven downwardly through the upper opening 62 in the cap 30 with sufiicient impact to drive the pin 65 past the'portion 66B of the spring 66 projecting into the key-way. The end of the pin '65 opposite the end to be impacted may be provided with beveled edges as 65B which facilitate positioning and insertion of the pin.

It is of course important that the spring 66 retain its resiliency throughout its life, and to this end the interior space enclosed by the spring is filled with a rubber-core 75, Fig. 4. The rubber core or filler 75 is a solid block having an outer side complemental at all areas to the inner periphery of the spring 66 as shown in Fig. 4 so as to fill the interior of the spring with resilient material except for the portion between the spaced ends 66E of the spring and the portion inwardly thereof. Thus, the rubber block 75 used to fill the spring is provided with a medial recess at the forward face thereof defined by upper and lower spaced walls 76 and 77 and a rear wall 78 rearward of ends 66E of the spring. The recess thus defined in outline is of slightly larger dimension than the boss 68 formed in the nose of the adapter 31 to facilitate mounting of the filled spring on the boss 68, but when the pin 65 is wedged in place the rubber block 75 in part flows about the boss '68. In this manner, the rigid or metal parts of the spring 66 that are spaced from the boss 68 of the adapter are effectively filled interiorly with resilient material which prevents accumulation of debris between the spring 66 and the boss 68 of the adapter, thereby assuring that the spring maintains its effectiveness throughout its life.

As shown in Fig. 5, the pin 65 in the forward face thereof is formed with a transverse .groove 65G, and when the pin 65 is first positioned for insertion into the key-way 60, the groove 656 is faced in a forward direction. Accordingly, impact delivered to the pin 65 forces the pin downwardly through the key-way to the extent that the arcuate back 66B of the spring 66 seats in the groove 65G, and this accurately positions the pin 65 the upper and lower ends thereof reposed, respec tively, in the upper and lower openings 62 and 6.3 in the cap 30. When the spring 65 has thus been operatively compressed between the forward face of the pin and the vertical portion in the adapter afforded by the aligned shoulders 71 and 72 forwardly of the pin, the spring 66 assumes the entire load of retention and is placed under high compression, and a portion of the result-ant force in this instance is exerted rearwardly against the medial portion of the pin 65 defined by the groove 65G therein such that the opposite ends of the pin are held with equal force against the rear walls of the respective openings 62 and 63 in the tooth cap. At the same time, the end po rtions 66E. of the leaf spring exert a resultant forward force against the correspondingly paired shoulders 71 and 72 within the adapter thus serving to pull the cap 30 fully up on the nose 45.

It is also to be noted that when the spring 66 is thus placed under compression by the pin 65 as aforesaid, the nodal portions 66N are expanded outwardly against the portions of the upper and lower walls of the cap 30 that overlie these nodal portions of the spring 66. Accordingly, it will be seen that. under and'in accordance with the present invention, the main forceof the spring is applied against the pin along the horizontal center line of the cap and the adapter, such being effective with respect to said center line to equally distribute retaining forces of substantial magnitude against the pin, the adapter and the cap.

To release the pin, it is merely necessary to punch sharply the lower end thereof, and in this connection it will be noted that the pin 65 is preferably wedge-shaped as best shown in Fig. 3 to aid in accurate insertion from top to bottom the key-way 60. I

The cap 30 is fully reversible in that all parts are symmetrical enabling the cap to be removed from the adapter 31 and reversed face for face to present a new digging point when the lower edge 38 becomes dull. Such is attained by arranging the openings 62 and 63 on a true vertical line correspondingly as the key-way 60, and by having the nose of the adapter and the socket in the cap or point in the form of an isosceles triangle with the boss 68 located along the center line or perpendicular thereof.

6 equally distributed with respect to the center line of the tooth,'the interior of said leaf spring being filled with resilient material.

4. A dipper tooth comprising an adapter having a forwardly projecting nose portion, a removable wear cap having upper and lower roarwardly diverging walls mating with the nose of the adapter when the cap is mounted thereon, a vertical key-way through the nose of the adapter, a boss of reduceddimensions within the nose of the adapter adjacent said key-way affording a vertical portion within the adapter serving to back up the respective ends of a generally arcuate C-shaped leaf spring with the arcuate back of the spring normally expanded beyond the boss partway into said key-way along the horizontal Hence, while I have illustrated and described the preferred embodiment of my invention, it is to be understood that this is capable of variation and modification, and l therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. A dipper tooth for excavating equipment comprising an adapter, a forwardly projecting portion on the adapter, a removable wear cap including spaced apart walls affording a rearwardly opening socket mating with said portion of the adapter when the cap is mounted on the adapter, a key-way through said portion of the adapter, openings in the walls of said cap adapted to register with open ends of said key-way, a pin for the keyway including end portions adapted to engage portions of the walls of said cap, and an arcuate leaf spring having an arcuate back forcefully bearing against one face of the pin and having ends forcefully bearing against a vertical solid portion within the adapter spaced from said arcuate back to hold the ends of the pin forcefully rearwardly against said portions of the walls of the cap and thereby releasably hold the cap on the adapter, the interior of said leaf spring being filled with resilient material.

2. A dipper tooth for excavating equipment comprising an adapter, a forwardly projecting nose on the adapter, a removable wear cap including spaced apart walls affording a rearwardly opening socket mating with said nose when the cap is mounted on said adapter, a key-way through the nose of the adapter, openings in the walls of said cap adapted to register with open ends of said key-way, a pin for the key-way including end portions adapted to bear against portions of the walls of said cap adjacent the openings therein, and an arcuate- 1y shaped leaf spring under compression between the pin and a solid portion within the adapter forwardly thereof to hold the ends of the pin against said portions of the cap adjacent the openings therein with a rearward force equally distributed with respect to the center line of the cap and the adapter, said spring being under compression as aforesaid by having an arcuate back thereof bearing forcefully on said pin and free ends thereof bearing forcefully on said solid portion of the adapter, the interior of said leaf spring being filled with resilient material.

3. A dipper tooth for excavating equipment comprising an adapter including a forwardly tapered nose portion, a removable wear cap including rearwardly diverging upper and lower walls adapted to mate with the nose of the adapter when the cap is mounted thereon, a vertical key-way through the nose of the adapter, openings at the top and bottom of said cap adapted to register with ends of said key-way when the cap is on the adapter, a pin for the key-way including end portions adapted to repose in the openings in said cap, shoulders in the adapter forwardly of the key-way, and a substantially C-shaped leaf spring acting between the pin and said shoulders in the adapter forwardly thereof with forces center line of the adapter, and upper-and lower openings formed in said walls of the cap adapted to register with the ends of the key-way to enable a pin to be driven into the key-way past said spring with the upper andlower ends thereof reposed respectively in the upper and lower openings of the cap, the spring being effective on the medial portion of the pin thus inserted in the key-way to hold the pin against the rear walls of the openings in the cap with a force applied rearwardly along the center line of the adapter, and the interior of said leaf spring being filled with resilient material.

5. A dipper tooth comprising an adapter having a forwardly tapered nose portion, a removable wear cap including rearwardly diverging upper and lower walls fitting over said nose when the cap is mounted on the adapter, a vertical key-way extending through said nose portion, a boss within the nose of the adapter inwardly of the forward end of he nose and being of reduced dimension with respect to said nose so as to afford a vertical portion within the adapter forward-1y of the keyway serving as a reaction surface for a generally arcuate *C-shaped leaf spring mounted on said boss with the arcuate back of the spring expanded beyond the boss part way into said key-way, the interior of said leaf spring being filled with resilient material, and upper and lower openings in said cap adapted to register with said key-way to enable the ends of a pin driven past the back of said spring into said key-Way to repose in the upper and lower openings of the cap, the spring being effective on the medial portion of the pin thus inserted in the key-way to hold the pin with substantially equal force against the rear walls of the openings in the cap and reacting in a forward direction with substantially equal force against said vertical portion in the nose of the adapter.

6. In a retainer element for a dipper tooth comprising v a removable wear cap and an adapter for the cap together having registered openings therein defining a mounting socket, a generally C-shaped one-piece leaf spring insertable in said mounting socket and including an arcuate back portion, said spring having spaced apart rounded end portions forwardly of said back that are substantially centered with respect to the back of the spring, and the interior only of said spring being filled with resilient material which does not project beyond the boundaries of said spring.

7. In a retainer element for a dipper tooth comprising a removable wear cap and an adapter for the cap together having registered openings formed therein defining a mounting socket, a leaf spring insertable in said mounting socket and including an arcuate back portion having a more sharply rounded node element medially thereof, said spring having spaced apart sharply rounded end portions substantially centered on either side of the node element at the back of the spring, the sharply rounded end portions of the spring being engageable with portions of the adapter adjacent the opening therein, and the interior of said leaf spring being filled with resilient material.

which together define a mounting socket, a pin and an associated arcuate leaf spring under compression in said mounting socket, said spring including an arcuate back portion havi-ng 'a more sharply rounded node element medially thereof seated in a recess in the pin, said spring having spaced apart rounded end portions substantially centered with respect to the node element of the'back of the spring and bearing on shoulders of the adapter forwardiy of the said pin, and the interior of said leaf spring being filled with resilient material.

' 9. A dipper tooth for excavating equipment comprising an adapter including a forwardly projecting nose portion, a removable wear cap including a rearwardly opening socket mating with the nose of the adapter when the cap is mounted thereon, a vertical key-way through the nose of the adapter, openings at the top and bottom of said cap adapted to register with ends of said keyway when the cap is on the adapter, .a pin for the keyway including end portions adapted to repose in the openings in said cap, and an arcuate one-piece leaf spring mounted under compression within said adapter inde pendently of said pin and havingan arcuate' portion forcefully engaging the forward face of said pin and having end portions thereof engaged with a solid portion of the adapter to hold the cap on the adapter with forces equally distributed with respect to the center lined the tooth, the interior of said leaf spring being filled with resilient material.

References Cited in the file of this patent UNITED STATES PATENTS 7 796,798 Blaine i Aug. s, 1905 2,427,651 Baer Sept. 23 1947 2,483,032 Baer Sept. 27, 1949 2,657,482 Launder et al. Nov. 3, 1953 2,702,490 Launder Feb. 22, 1955 2,870,667 Murtau'gh Jan. 27, 1959 FOREIGN PATENTS 565,417 Great Britain Nov. 9, 1 944 

